Europe Pushing For Lunar Time Zone (apnews.com) 43
With more lunar missions than ever on the horizon, the European Space Agency wants to give the moon its own time zone. The Associated Press reports: This week, the agency said space organizations around the world are considering how best to keep time on the moon. The idea came up during a meeting in the Netherlands late last year, with participants agreeing on the urgent need to establish "a common lunar reference time," said the space agency's Pietro Giordano, a navigation system engineer. "A joint international effort is now being launched towards achieving this," Giordano said in a statement.
For now, a moon mission runs on the time of the country that is operating the spacecraft. European space officials said an internationally accepted lunar time zone would make it easier for everyone, especially as more countries and even private companies aim for the moon and NASA gets set to send astronauts there. [...] The international team looking into lunar time is debating whether a single organization should set and maintain time on the moon, according to the European Space Agency.
There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. Perhaps most importantly, lunar time will have to be practical for astronauts there, noted the space agency's Bernhard Hufenbach. "This will be quite a challenge" with each day lasting as long as 29.5 Earth days, Hufenbach said in a statement. "But having established a working time system for the moon, we can go on to do the same for other planetary destinations."
For now, a moon mission runs on the time of the country that is operating the spacecraft. European space officials said an internationally accepted lunar time zone would make it easier for everyone, especially as more countries and even private companies aim for the moon and NASA gets set to send astronauts there. [...] The international team looking into lunar time is debating whether a single organization should set and maintain time on the moon, according to the European Space Agency.
There are also technical issues to consider. Clocks run faster on the moon than on Earth, gaining about 56 microseconds each day, the space agency said. Further complicating matters, ticking occurs differently on the lunar surface than in lunar orbit. Perhaps most importantly, lunar time will have to be practical for astronauts there, noted the space agency's Bernhard Hufenbach. "This will be quite a challenge" with each day lasting as long as 29.5 Earth days, Hufenbach said in a statement. "But having established a working time system for the moon, we can go on to do the same for other planetary destinations."
UTC - it's in the name (Score:5, Insightful)
I would think the time on the moon would be in Coordinated Universal Time (UTC). If any sites are on the side of the moon that permanently faces the Earth then it should be fairly easy to receive a faint signal from either GPS (United States), GLONASS (Russian Federation), Beidou (China) or Galileo (European Union) satellites.
If the moon needs its own GPS equivalent in the future, then it will be even easier for the sites to keep a common time standard.
Re:UTC - it's in the name (Score:5, Informative)
Special relativity. Read a summary of it. Still, I think all clocks need to have their time plus a log of the adjustment in comparison to a (virtual?) reference clock either on Earth or in solar orbit (so speed of earths rotation won't complexity things). The reason is as we keep exploring the asteroid and planets, and have space stations in the solar system. This time issue will be a problem.
Re:UTC - it's in the name (Score:5, Interesting)
Re:UTC - it's in the name (Score:4, Informative)
Due to special relativity, from a given reference frame, the time elapsed between say noon and midnight is different on the Earth than on the moon. It takes exactly 12 hours within whatever reference frame you are in, and only there.
Re:UTC - it's in the name (Score:4, Informative)
then it should be fairly easy to receive a faint signal from either GPS (United States), GLONASS (Russian Federation), Beidou (China) or Galileo (European Union) satellites.
Nope. Satellites with their already quite weak power output have very carefully designed antennas pointing to earth with quite a significant gain. So you have:
A distance that is 20x greater to the source.
A signal that has 20x lower power.
A signal that is already insanely weak on earth, blocked by the most trivial of interference or obstruction.
Picking up a GPS signal on the moon would be an engineering feat in and of itself.
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Power doesn't drop lineally with distance (R). It drops off at a rate of 1/R^2 (1 over R squared) so if the moon is 20x the distance, the power will be somewhere around 1/20^2 or 1/400. This is also neglecting that fact the antennas will be pointing in the wrong direction.
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I didn't say it was, but thanks for showing just how bad the "20x distance" actually is.
Easy feat of engineering to pick up GPS signals (Score:3, Informative)
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No it's not 20x and 20x in terms of power. It's 20x in terms of power and 20x in terms of distance which makes it roughly 800x in terms of power.
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Re:UTC - it's in the name (Score:5, Insightful)
This was my initial knee-jerk, too: don't need an "international effort" to just use UTC.
But I think the point of this is to come up with a time system that would make sense to someone living on the Moon, not something Earth-centric. "Time zone" was probably a bit too simplistic of a term - they need a whole new calendar that makes sense for the Moon (and respective other planets), but also can interface with Earth without being a royal PITA.
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This is exactly it. It’s relatively easy to dictate that X is a “universal” time, as we’ve already done. It’s much more difficult to make that “universal” time universally meaningful, reasonable, reflective of actual experience, and measurable. We get most of those here on the surface of Earth with UTC; not so much if you tried to apply UTC to the lunar surface, given that it’s out of sync with lunar days.
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The GPS signals you would receive on the moon would be from the other side of planet earth, and far more than one second outdated.
No idea why GPS came to your mind, a few earth based stations would be much more convenient.
Most likely a suitable accurate clock on the moon will do. It is not so that we _need_ millisecond accuracy. After all we are talking about a TIME ZONE, so everyone agrees on a zone, and misunderstandings like CEST versus CET versus GMT/UTC get avoided.
Re:UTC - it's in the name (Score:4, Interesting)
It is not so that we _need_ millisecond accuracy...
Uh, wrong. There is a difference between time (as in your wristwatch) and timing (as in what clocks high-speed communications). And if you intend to convince anyone from GenInternet to go off-planet, you better have a WiFi password ready upon touchdown.
After all we are talking about a TIME ZONE, so everyone agrees on a zone, and misunderstandings like CEST versus CET versus GMT/UTC get avoided.
Can't even get states or counties to agree on a time zone within a time zone on earth. But the military figured this out decades ago. Zulu Time/UTC makes sense, so there's little reason to carry the ignorance of "zones" to the moon. We'll likely be all living on the same block when we do finally get there anyway.
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Zulu Time/UTC makes sense, so there's little reason to carry the ignorance of "zones" to the moon
then the time zone of the Moon would be "zulu". No idea what your comprehension problem is.
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Zulu Time/UTC makes sense, so there's little reason to carry the ignorance of "zones" to the moon then the time zone of the Moon would be "zulu". No idea what your comprehension problem is.
The comprehension problem lies with the person who fails to understand singular from plural.
I said don't carry the ignorance of zones. One zone (Zulu) works just fine, as global military forces have proven it does for decades.
We couldnt even ratify summer or wintertime (Score:3)
Europe had plans to skip adjusting for summer or wintertime years ago, it was all the rage in the news and most countries agreed, it was unscientific to "adjust" the clock for summer or winter savings time, but that died out in silence, nothing was ever heard of it after that.
So now? A Lunar time?
Greenwich Mean Time (Score:5, Insightful)
aka Coordinated Universal New Time, and the Gregorian Calendar (even Russia uses that now) will work just fine.
Computer software already deals separately with time-of-day, and high-precision elapsed time. It is a solved problem.
A few apps need to be careful not to assume that a day has exactly 24x3600 seconds. GPS as the obvious example, has to deal with Relativity, and astronomical leap seconds.
Almost anything that cares about time of day scheduling does not care about microseconds, and vice versa.
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Coordinated Universal New Time
I approve this acronym.
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Then you'll love Australia's Northern Territory, and their tourism marketing slogan: "CU in the NT".
Stardate (Score:2)
Prior art (Score:1)
See The Demolished Man by Alfred Bester (1953). In that, the protagonist checks the time on his clock, which shows for three planets and three moons. However, that's just the meridian time (UTC on Earth) so he still has to know what time zone he's in for the celestial body he's on and add / subtract "hours", but it's a start. It's also not difficult.
So have a meridian time, because that's what time it is there not here. When we get around to having permanent occupation off-planet, then we can argue about ti
TZhanks but no tzthanks. (Score:1)
TL;DR skip to ### to avoid the factual yet ranty history.
I appreciate that Europe wants to mess with yet another standard that already doesn't work, but of course its shown that leadership to be faulty -- at best.
TZdata is the timezone database that is CONSTANTLY changing. Most of this is a result of countries modifying by legal means their offset to UTC. For an example see the tzdata changelog at https://github.com/lau/tzdata/... [github.com]
Now, pretend that time on the moon is not related to time on Earth. This is
Re: TZhanks but no tzthanks. (Score:2)
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> doesnâ(TM)t use it, and thatâ(TM)s
I'm pretty sure your UTF-8 failures in one post prove my point. Thanks.
Next time try "doesn't use it, and that's.
Metric system. Yes, because carpenters and woodworkers and ironworkers and tradesmen can't be trusted to bend something in 2, 4, 8, 16, 32, but have to do it in 1/10ths. Brilliant. I can't imagine how that one has successfully trounced the world. Give you 2.54cm and you take 0.4532kg.
E
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UTF-8 is a standard from a committee dominated by US-based companies, and the abomination of inserting "smart quotes" guessing from context which is appropriate because you don't give the user a keyboard which lets them choose is also something thrust upon the world by US-based companies. Is what way are the UTF-8 failures of GPP a European failure?
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Europe failed at every standard? Like, you know, the metric system? SI? The most successful standard ever created? There is only one big developed country on Earth that doesnâ(TM)t use it, and thatâ(TM)s a failing of that country, not of Europe.
Fun fact: The U.S. would be using the metric system too, if not for pirates! Jefferson wanted to unify and standardize the measurement systems then in use but those devious pirates of the Caribbean foiled the plan.
https://www.npr.org/sections/t... [npr.org]
Space agencies internally use JDNs (Score:1)
Time zones are stupid (Score:2)
A lunar time zone (Score:2)
Not ambitious enough. (Score:3)
People here are shitting all over the idea, but I think this is a good time to think about such things, and set up structures where local time zones can be generated as populations arrive and grow -- but just one TZ for the whole moon isn't going to work. They'll probably need one TZ for every major clump of settlements. The same is true of Mars. One time zone doesn't cut it on Earth, and it's pretty much only used as the least worst option for Antarctica because every method of reconciling TZs against local needs must violate one or the other quite badly. Two settlements on Mars that set up thousands of km apart because they don't want to be close aren't going to want to be in the same time zone either.
"ticking occurs differently on the lunar surface" (Score:2)
Defining exact periods of time on the moon is very difficult. They must be "LunarTicks".
Star Trek (Score:2)
But when will Lunar Daylight Savings time start? (Score:2)
UTC would work just fine (Score:2)
Second, because of that, there is no need for multiple time zones. Everyone may as well be on the same time, because it's not related to whether it's sunlight time or not.
Third, relativity is not a problem. Just adjust the logic in digital clocks on the moon to account for the extra 56 microseconds in each human day (that's an extra 20 milliseconds per year). And just periodically re
The Lunar Day is 27 Earth Days? (Score:3)
Just what the hell would a Lunar month be ?
Just what constitutes a time zone on the moon? 1 hour, or 1.1 days?
What is the use? The whole point of time zones was to prevent trains from colliding and maximize use of light. How do you maximize the use of light when your biology is adapted to a 24 hour days and you are living someplace that has a 600 + hour day.
This looks like it would just complicate mission administration, and UTC should be close enough for international cooperation.